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991.
Rapid, chip-scale, and cost-effective single particle detection of biological agents is of great importance to human health and national security. We report real-time, high-throughput detection and sizing of individual, low-index polystyrene nanoparticles and H1N1 virus. Our widefield, common path interferometer detects nanoparticles and viruses over a very large sensing area, orders of magnitude larger than competing techniques. We demonstrate nanoparticle detection and sizing down to 70 nm in diameter. We clearly size discriminate nanoparticles with diameters of 70, 100, 150, and 200 nm. We also demonstrate detection and size characterization of hundreds of individual H1N1 viruses in a single experiment.  相似文献   
992.
Foreword     
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993.
A numerical method for calculation of the polarization conductivity has been developed. This approach has been applied to the correlated barrier hopping (CBH) and quantum mechanical tunnelling (QMT) models in the case of monoelectronic hops. These calculations have been performed on well-known solids such as carbon (HTT 600° C) and badly organized molybdenum and tungsten sulphides. The agreement between theory and experimental results is more satisfying than in a previous approach. The parametersW M andN 0 are determined for the CBH model, andN(E F) for the QMT model.  相似文献   
994.
Data are given on the test object for scanning electron microscopy in which the components (ridges) are of trapezoidal profile and have large angles of inclination for the side walls. The width of the top surface of a projection is less than 10 nm. Methods have been developed for measuring such dimensions of test objects on standard scanning electron microscopes. __________ Translated from Izmeritel'naya Tekhnika, No. 8, pp. 20–23, August, 2008.  相似文献   
995.
Automated recovery of system features and their designs from program source codes is important in reverse engineering and system comprehension. It also helps in the testing of software. An error that is made by users in an input to an execution of a transaction and discovered only after the completion of the execution is called a posttransaction user-input error (PTUIE) of the transaction. For a transaction in any database application, usually, it is essential to-provide transactions for correcting the effect that could result from any PTUIE of the transaction. We discover some probable properties that exist between the control flow graph of a transaction and the control flow graphs of transactions for correcting PTUIE of the former transaction. Through recognizing these properties, we present a novel approach for the automated approximate recovery of provisions and designs for transactions to correct PTUIE of transactions in a database application. The approach recognizes these properties through analyzing the source codes of transactions in the database application statically.  相似文献   
996.
A recursive orthogonal least squares (ROLS) algorithm for multi-input, multi-output systems is developed in this paper and is applied to updating the weighting matrix of a radial basis function network. An illustrative example is given, to demonstrate the effectiveness of the algorithm for eliminating the effects of ill-conditioning in the training data, in an application of neural modelling of a multi-variable chemical process. Comparisons with results from using standard least squares algorithms, in batch and recursive form, show that the ROLS algorithm can significantly improve the neural modelling accuracy. The ROLS algorithm can also be applied to a large data set with much lower requirements on computer memory than the batch OLS algorithm.  相似文献   
997.
Being the primary interdomain routing protocol, Border Gateway Protocol (BGP) is the singular means of path establishment across the Internet. Therefore, misconfiguration errors in BGP routers result in failure to establish paths which in turn can cause several networks to become unreachable. In this paper, we first analyze data from recent BGP tables to show that misconfiguration errors occur very frequently in the Internet today. We then show theoretically and using real-world events the impact of these errors on routing stability. A scheme for real-time isolation of large-scale BGP misconfiguration events is then proposed in this paper. Our methodology is based on statistical techniques and is evaluated using data from past wellknown misconfiguration events. We show the effectiveness of our method as compared to the current state-of-the-art.  相似文献   
998.
B.C. Majumdar 《Wear》1975,33(1):37-43
A theoretical analysis of load-carrying capacity generated by vibration of the journal (the squeeze-film effect) of an externally pressurized porous gas journal is made. The flow of gas in the porous media is in three dimensions and obeys Darcy's law. The solution has been obtained by the perturbation method. The journal is assumed to vibrate either by translatory motion or by rotational motion around the transverse axis. The dimensionless squeeze load, moment, load- and moment-phase angles are given for various squeeze numbers, feeding parameters and a porosity number.  相似文献   
999.
1000.
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